SN74HCT138NSR

Product Overview

• Category: Integrated Circuit (IC)
• Use: Decoder/Demultiplexer
• Characteristics: High-speed, CMOS logic, 3-to-8 line decoding
• Package: SOIC (Small Outline Integrated Circuit)
• Essence: Decodes a 3-bit binary input to one of eight outputs
• Packaging/Quantity: Tape and Reel, 2500 units per reel

Specifications

• Supply Voltage Range: 2V to 6V
• Input Voltage Range: 0V to VCC
• Output Voltage Range: 0V to VCC
• Maximum Operating Frequency: 25 MHz
• Propagation Delay Time: 13 ns (typical)
• Low Power Consumption: ICC = 4µA (max)

Detailed Pin Configuration

The SN74HCT138NSR has a total of 16 pins. The pin configuration is as follows:

1. GND (Ground)
2. A0 (Input A0)
3. A1 (Input A1)
4. A2 (Input A2)
5. /G1 (Enable Input)
6. Y0 (Output Y0)
7. Y1 (Output Y1)
8. Y2 (Output Y2)
9. Y3 (Output Y3)
10. Y4 (Output Y4)
11. Y5 (Output Y5)
12. Y6 (Output Y6)
13. Y7 (Output Y7)
14. VCC (Supply Voltage)
15. /G2A (Enable Input)
16. /G2B (Enable Input)

Functional Features

The SN74HCT138NSR is a 3-to-8 line decoder/demultiplexer IC. It takes a 3-bit binary input and selects one of the eight outputs based on the input combination. The /G1 and /G2A, /G2B enable inputs control the operation of the decoder.

Advantages and Disadvantages

Advantages: - High-speed operation - Low power consumption - Wide supply voltage range - Compact SOIC package

Disadvantages: - Limited number of inputs and outputs - Not suitable for complex decoding applications

Working Principles

The SN74HCT138NSR uses CMOS logic to decode the 3-bit binary input. The enable inputs (/G1, /G2A, /G2B) determine whether the decoder is active or not. When enabled, the decoder selects one of the eight outputs based on the input combination.

Detailed Application Field Plans

The SN74HCT138NSR is commonly used in various digital systems where decoding and demultiplexing functions are required. Some application areas include:

1. Address decoding in microcontrollers and microprocessors.
2. Memory selection in RAM and ROM modules.
3. Data routing in multiplexed data buses.
4. Signal decoding in communication systems.
5. Control signal generation in industrial automation.

Detailed and Complete Alternative Models

1. 74HC138: Similar functionality, but operates at a higher voltage range (2V to 6V).
2. CD74HC138: Equivalent functionality, but available in a different package (DIP - Dual Inline Package).
3. SN54HCT138: Same functionality, but operates at a lower temperature range (-55°C to 125°C).

These alternative models provide similar decoding capabilities with slight variations in voltage range, package type, and operating temperature.

In conclusion, the SN74HCT138NSR is a high-speed 3-to-8 line decoder/demultiplexer IC. It offers a compact design, low power consumption, and wide supply voltage range. Its applications range from address decoding in microcontrollers to signal decoding in communication systems. Alternative models with similar functionality are available to suit specific requirements.